1. Field of the Invention
The present invention relates to the body structure of railway vehicles and enclosed girder bridges, constructed of press-formed frameworks.
2. Description of the Prior Art
FIGS. 13A-14C show a side body structure for conventional vehicles. As shown in the figures, various posts such as a side entrance post 2, door end post 3, and side post 4 are vertically mounted relative to a horizontally laid rocker rail 1. Horizontally disposed between these posts are window sill 5, a door pocket window sill 6, a frieze 7, and a door header 8. Further, a door pocket post 9 and a frieze frame 10 are vertically provided relative to the aforementioned horizontally disposed members. The above mentioned members are welded together to complete the framework of a side body structure. Substantially the entire surface of the thus made framework is then covered with an outer plate sill 13, a door pocket window outer plate sill 14, and a frieze outer plate 15, to which are welded reinforcements 11 and 12. In this manner, a side body structure having a window 16 is completed.
FIGS. 15A.15E show an example of an end body structure provided at the front and rear bridges of a railway vehicle. The end body structure has a pair of end entrance posts 17 and 17 on the left and right sides of the end entrance, and vertically provided corner post 18 and 18. Between those posts are disposed a plurality of members such as a door header 19, an end rocker rail 20, and cross beams 21. An arch shaped beam 22 is disposed on the posts 17 and 18 and an end outer plate 23 is welded on the end body structure. In this manner, the end body structure is completed.
Japanese Patent Preliminary Publication No. 61-220962 discloses a structure in which a flat side outer plate and a reinforcement having an uneven surface are put together to form a side body structure. The reinforcing plates have relatively small projections transversely thereof, that is, beads, the cross section of which is that of triangle, and projections having a U-shaped cross section longitudinally of the small projections. The reinforcing plate may have an uneven surface with rectangular projections thereon and a core material is interposed between the side outer plate and the reinforcement.
Japanese Patent Preliminary Publication No. 61-220963 discloses a structure in which a bead is formed on pier panels between the side posts and cross members in the direction of a shear force.
Such conventional structures have drawbacks in that the side body structure requires a large number of components of different kinds, more preliminary preparation operations when machining, and complex working operations. The conventional structures also require a large number of jigs for positioning the respective members relative to each other, and is complex in getting all necessary parts ready for the assembly operation. In addition, welding must be carried out at many positions, such leading to increased mechanical strains and less dimensional precision.
According to the aforementioned Japanese Patent Preliminary Publications, No. 61-220962 and 61-220963, beads are used to form uneven surfaces. However, the projections provided by the beads are rather small, thereby being less effective. Japanese Preliminary Publication No. 61-220962 requires an additional operation of inserting the core material between the projections and the outer plate.